Fan structure



E. s. PRl-zsTdN July 5, 1938.

FAN STRUCTURE Filed NOV. 15, 1957 Patented July 5, 1938 i UNITED STATES PATENT orslcs FAN smuc'mma Edward s. Preston, Hinsdale, m. assignor to cmcago Electric Manufacturin L Company, Chic'ago, 111., a corporation oflllinolsv Application November 15, 1937, Serial No. 174,536

2 Claims.

The present invention relates to a fan structure and more particularly to; a metal fan blade structure of the type employed in the conventional electricians.

It is an object of the present invention to provide a fan blade structure which may be readilystamped or otherwise. formed out of any suitcentral position where it will not interfere-with the action of the fan and serves to give a finished appearance to thearticle, as well as providing an admirable position for the situation of the necessary informative designations relating to the device, such, for example, as the manufacturer's name. I

A yet further object of the present invention is to provide a central ,name plate fora fan blade structure, which name plate may be formed of sheet material and is centered by a surrounding annular rib in the blade structure and which is attached to the blade by tab means so that it may be secured in position at any time during manufacture or may be readily changed at any subsequent time in order to revise the style thereof or the designations thereon.

Numerous other objects and advantages will more fully appear during the course and progress of the following specification. Referring to the drawing:

Figure 1 is a front elevational view of a blade structure constructed in accordance with the present invention.

Figure 2 is a detail rear elevational view ofthe blade structure showing the central portions thereof.

Figure 3 is'a detail sectional. view taken on the lineHin'FlgureL' Figure 4 is a perspective view of the detachable 5 hub member shown in disassembled relationship. The device shown as illustrating one structural embodiment of the present invention, comprises, as clearly shown in Figure '1, a four-bladed propeller which maybe and preferably is formed of a any suitable sheet material. The blades are designated by the numeral l0 and each is provided with a substantially straight leading edge I! and anarcuate following edge l4 which is offset forwardly so that the structure will tend to impel air or other gas in a forward direction when 5 rotated in'a clockwise direction.

According to one preferred form of the invention the blade structure may be made of sheet metal of a sufficient degree of rigidity to maintain the configuration as shown. Attention is 10 directed to the annular rib I6 protruding outwardly from the normal front surface of the structure, as shown more clearly in Figures 2 and 3, and formed by stamping, pressing or otherwise distorting the sheet material to form [I an annular groove l8 in the rear face thereof. Opposite each of the respective blades, the groove is extended radially a short distance as at 20 forming radial ribs 22 on the front surface of the fan in order to lend strength and rigidity to 20 the unit.

In order to support the propeller structure for rotation in the conventional manner, there is provided a central aperture 24 in which a bushing 26 is situated, being mounted rigidly in place 25 by upsetting or turning over the protruding end thereof, as indicated by the numeral 28 in Figure 3. The bushing is provided with a suitable. axial bore to accommodate the end of any con-' venient motor or drive shaft indicated in the 30 dotted lines in Figure 3, assembly being maintainedby means ofthe set screw 30.

The space centrally of the annular rib portion I6 and comprising the .more or less unsightly end of the bushing 28 is 'conbletely enclosed by a hub 5 member 32. The structure of this hub member before union with the propeller is shown more clearly inFigure 4 and comprises a generally cup-shaped member having a short cylindrical wall 34 which is closed at one end by a convex 4Q .outer wall 36. The cylindrical wall 34 is extended at diametrically opposed portions to provide tablike continuations 38. It will be thus apparent.

that the hub member 32, being open on one side, provides a concave enclosure. This member, ac- 5 cording to the preferred embodiment, may be formed of some stiff and rigid material, preferably .sheet'metal. 5

In order to assemble the hub member the tablike continuations or extensions 38 are inserted into a pair. .of rectangular apertures 40 provided in the sheet material of the propeller and spaced appropriately to accommodate them. After the hub is positioned flush with the front face of the propeller, the tabs 38 are bent over outwardly,

bushing '38, rendering unnecessary further costly machining or other operations such as would otherwise be resorted to for the sake of appearance should the hub member be omitted.

Thus the union of the bushing 26 with the propeller. structure may be made solely with the view to improve structural strength and rigidity. Moreover, the present hub accomplishes these results while giving a highly pleasing finished appearance.

It hasbeen found convenient in accordance with the present invention to employ this hub construction as a name plate for designation of the name of the manufacturer of the device and/or notations of other distinguishing characteristics relating thereto.

In this connection it will be apparent that the hub unit 32 may be applied at substantially any time after the main portion of the propeller has been formed. It may frequently occur that the particular designation of the device is not to be applied until some time after manufacture or until just before final sale of the completed article. Frequently it is desired to change the nameplate and apply another before sale.

when constructing propeller blades in accordance with the present invention, therefore, the

name plate need not be attached until any preferred time before final disposition thereof when it may be rigidly secured in place by a few simple operations with only conventional tools. So, too, previously applied name plates may be readily removed and supplanted without disassembling the device nor in any way interfering with the structural unity thereof. i

While the propeller structure described in detail in the present specification has been indicated for illustrative purposes as comprising a sheet material such as sheet metal, nevertheless it will be apparent that any other suitable sheet material may be employed, such, for example, as

"resilient variety.

-It is thought that the invention and numerous any of the various plastics whether of rigid or of its attendant advantages will be understood from the foregoing description and it is obvious that numerous changes may be made in the form, construction and arrangement of the several parts without departing from the spirit. or scope of the invention, or sacrificing any of its attendant advantages, the form herein described being a preferred embodiment for the purpose of illustrating the invention.

The invention is'hereby claimed as follows:

1. A fan comprising a propeller member having a plurality of blades formed of. sheet material, a central apertured bushing mounted in said propeller and providing an axial aperture extending therethrough for engagement of and attachment to a drive shaft extending from the point on the inward side of the propeller, said propeller being distorted outwardly of its normal plane to provide an inwardly facing, annular channel about said bushing adapted to cause an annular rib to be formed on the outer face thereof, said annular rib refining within its limits an outwardly facing depression, a concave sheet cap member on said outer face located entirely within said depression and enclosing the outer end of said apertured bushing, and tabs on said cap member extending through the propeller and bent over to maintain the cap in said position.

2. A fan comprising a propelling member having a plurality of blades formed of sheet material, said propelling member having central means for engagement with and attachment to a drive shaft, said propelling member being distorted'outwardly of its normal plane to provide an annular channel facing inwardly toward said drive means, said annular channel encircling said engagement and attachment means and being formed by distortion of the sheet material throughout its thickness whereby to form an annular rib on the outer face of said propelling member, said annular rib defining within its limits an outwardly facing depression and a concave sheet cap member on said outer face and located entirely within the depression and covering said drive shaft attachment means.

EDWARD S. PRESTON. 

